Spontaneous Formation of a Doubly Interlocking [2] Catenane Using Copper (I) and Palladium (II) as Templating and Assembling Centers

双互锁索烃是一种复杂的手性拓扑结构，最近才被描述。我们的方法是联合收割机的两种方法，基于配位化学，这被称为“模板”和“自组装”的战略。在模板策略中，铜（I）配合物被用作前体，提供从简单到拓扑非常复杂的索烃。另一方面，自组装过程在一个化学步骤中从非常简单的分子片段和温和的条件下获得复杂的结构，包括互锁环。基于这两种策略的一种新方法已被用于构建一个4-交叉[2]索烃。所使用的配体含有连接到两个侧基/4-吡啶基的中心1，10-菲咯啉位点。中心位点用于络合铜（I）中心，而侧吡啶基团与钯（II）配位。逐步络合过程实际上是定量的。它可以两种方式进行（铜（I），然后钯（II）或反向）：最终的络合物是一个手性物种，包括4个配体，2个铜（I）和4个钯（II）中心。它已在溶液中进行了表征，其结构已通过ESI-MS证明。

Doubly interlocking catenanes are chiral and complex topologies which have only been described recently. Our approach is to combine the two methods, based on coordination chemistry, which are termed as "template" and "self-assembly" strategies. In the template strategy, copper(I) complexes have been used as precursors, affording simple to topologically very complex catenanes.On the other hand, the self-assembly process furnishes in one chemical step sophisticated structures, including interlocking rings, from very simple molecular fragments and under mild conditions. A new method based on these two strategies has been used to construct a 4-crossing [2]catenane. The ligand used contains a central 1, 10-phenanthroline site attached to two pendent/4-pyridyl groups. The central site is used to complex a copper(I) center whereas the lateral pyridine groups are coordinated to palladium(II). The stepwise complexation procedure is virtually quantitative. It can be carried out both ways (copper(I) followed by palladium(II) or reverse) : The final complex is a chiral species incorporating 4 ligands, 2 copper(I) and 4 palladium(II) centers. It has been characterized in solution and its structure has been evidenced by ESI-MS.